Graph Neural Network (GNN) based social recommendation models improve the prediction accuracy of user preference by leveraging GNN in exploiting preference similarity contained in social relations. However, in terms of both effectiveness and efficiency of recommendation, a large portion of social relations can be redundant or even noisy, e.g., it is quite normal that friends share no preference in a certain domain. Existing models do not fully solve this problem of relation redundancy and noise, as they directly characterize social influence over the full social network. In this paper, we instead propose to improve graph based social recommendation by only retaining the informative social relations to ensure an efficient and effective influence diffusion, i.e., graph denoising. Our designed denoising method is preference-guided to model social relation confidence and benefits user preference learning in return by providing a denoised but more informative social graph for recommendation models. Moreover, to avoid interference of noisy social relations, it designs a self-correcting curriculum learning module and an adaptive denoising strategy, both favoring highly-confident samples. Experimental results on three public datasets demonstrate its consistent capability of improving three state-of-the-art social recommendation models by robustly removing 10-40% of original relations. We release the source code at https://github.com/tsinghua-fib-lab/Graph-Denoising-SocialRec.

/pdf/robust-preference-guided-denoising-for-graph-based-social-1u1jqjbb.pdf

Robust Preference-Guided Denoising for Graph based Social Recommendation

Recommender systems across many Internet services have become a critical part of online businesses, as consumers would refer to them before making decisions. However, the lack of explicit ratings for items on many services makes it challenging to capture user preferences and item characteristics. Both academia and the industry have drawn attention to rating predications as a fundamental problem in recommendation systems. With the emergence of social networks, social recommender systems have been proposed to utilize the relationship between users and items to alleviate the data sparsity problem for rating predictions. However, they either concentrate on the opinion mining for each user and item, or consider the connections between users only. In this paper, we present an effective framework, Triple-hierarchical Attention Graph-based social rating prediction (TAG), to exploit the social relationships between users, the user-item interest relationships, the correlation relationships between items, and reviews for rating predictions. In order to consider opinions from reviews and these complex relationships, we first employ two triple-hierarchical attention to extract user and item features from reviews. We then design an inductive GNN, which generates effective embedding for users and items. Experiments over Yelp show that TAG outperforms state-of-the-art methods across RMSE, MAE, and NDCG metrics. 

TAG: Joint Triple-hierarchical Attention and GCN for Review-based Social Recommender System

Improvement of worst group performance and generalization performance are core problems of current machine learning. There are diverse efforts to increase performance, such as weight norm penalty and data augmentation, but the improvements are limited. Recently, there have been two promising approaches to increase the worst group performance and generalization performance, respectively. Distributionally robust optimization (DRO) focuses on the worst or hardest group to improve the worst-group performance. Besides, sharpness-aware minimization (SAM) finds the flat minima to increase the generalization ability on an unseen dataset. They show significant performance improvements on the worst-group dataset and unseen dataset, respectively. However, DRO does not guarantee flatness, and SAM does not guarantee the worst group performance improvement. In other words, DRO and SAM may fail to increase the worst group performance when the training and test dataset shift occurs. In this study, we propose a new approach, the sharpness-aware group distributionally robust optimization (SGDRO). SGDRO finds the flat-minima that generalizes well on the worst group dataset. Different from DRO and SAM, SGDRO contributes to improving the generalization ability even the distribution shift occurs. We validate that SGDRO shows the smaller maximum eigenvalue and improved performance in the worst group.

pdf/sharpness-aware-minimization-for-worst-case-optimization-2bwop12w.pdf

Sharpness-aware Minimization for Worst Case Optimization

Domain generalization aims to solve the challenge of Out-of-Distribution (OOD) generalization by leveraging common knowledge learned from multiple training domains to generalize to unseen test domains. To accurately evaluate the OOD generalization ability, it is necessary to ensure that test data information is unavailable. However, the current domain generalization protocol may still have potential test data information leakage. This paper examines the potential risks of test data information leakage in two aspects of the current protocol: pretraining on ImageNet and oracle model selection. We propose that training from scratch and using multiple test domains would result in a more precise evaluation of OOD generalization ability. We also rerun the algorithms with the modified protocol and introduce a new leaderboard to encourage future research in domain generalization with a fairer comparison.

pdf/rethinking-the-evaluation-protocol-of-domain-generalization-3j8uzsws.pdf

Rethinking the Evaluation Protocol of Domain Generalization

In real world domains, most graphs naturally exhibit a hierarchical structure. However, data-driven graph generation is yet to effectively capture such structures. To address this, we propose a novel approach that recursively generates community structures at multiple resolutions, with the generated structures conforming to training data distribution at each level of the hierarchy. The graphs generation is designed as a sequence of coarse-to-ﬁne generative models allowing for parallel generation of all sub-structures, resulting in a high degree of scalability. Furthermore, we model the output distribution of edges with a more expressive multinomial distribution and derive a recursive factorization for this distribution, making it a suitable choice for graph generative models. This allows for the generation of graphs with integer-valued edge weights. Our method achieves state-of-the-art performance in both ac-curacy and efﬁciency on multiple datasets.

HiGeN: Hierarchical Multi-Resolution Graph Generative Networks

Matching is almost the first and most fundamental step in recommender systems, that is to quickly select hundreds or thousands of related entities from the whole commodity pool. Among all the matching methods, item-to-item (I2I) graph based matching is a handy and highly effective approach and is widely used in most applications, owing to the essential relationships of entities described in a powerful I2I graph. Yet, the I2I graph is not a ready-made product in a data source. To obtain it from users' behaviors, a common practice in the industry is to construct the graph based on the similarity of item embeddings or co-occurrence frequency directly. However, these methods tend to lose the complicated correlations (high-ordered or nonlinear) inside decision-making actions and cannot achieve the global optimal solution. Moreover, the correlations between items are usually contained in users' short-term actions, which are full of noise information (e.g. spurious association, missing connection). It is vitally important to filter out noise while generating the graph. In this paper, we propose a novel framework called Purified Graph Generation (PGG) dedicated to learn faithful I2I graph from sparse and noisy behavior data. We capture the 'confidence value' between user and item to get rid of exception action during decision making, and leverage it to re-sample purified sets that are fed into an unsupervised I2I graph structure learning framework called GPBG. Extensive experimental results from both simulation and real data demonstrate that our method could significantly benefit the performance of I2I graph compared to the typical baselines.

Purify and Generate: Learning Faithful Item-to-Item Graph from Noisy User-Item Interaction Behaviors

In the information-overloaded era of the Web, recommender systems that provide personalized content filtering are now the mainstream portal for users to access Web information. Recommender systems deploy machine learning models to learn users’ preferences from collected historical data, leading to more centralized recommendation results due to the feedback loop. As a result, it will harm the ranking of content outside the narrowed scope and limit the options seen by users. In this work, we first conduct data analysis from a graph view to observe that the users’ feedback is restricted to limited items, verifying the phenomenon of centralized recommendation. We further develop a general simulation framework to derive the procedure of the recommender system, including data collection, model learning, and item exposure, which forms a loop. To address the filter bubble issue under the feedback loop, we then propose a general and easy-to-use reinforcement learning-based method, which can adaptively select few but effective connections between nodes from different communities as the exposure list. We conduct extensive experiments in the simulation framework based on large-scale real-world datasets. The results demonstrate that our proposed reinforcement learning-based control method can serve as an effective solution to alleviate the filter bubble and the separated communities induced by it. We believe the proposed framework of controllable recommendation in this work can inspire not only the researchers of recommender systems, but also a broader community concerned with artificial intelligence algorithms’ impact on humanity, especially for those vulnerable populations on the Web.

/pdf/breaking-filter-bubble-a-reinforcement-learning-framework-of-25nonwbh.pdf

Breaking Filter Bubble: A Reinforcement Learning Framework of Controllable Recommender System

In recent years, the explosive increase of information facilitates the massive knowledge graphs, which in turn increase burden of people to understand and leverage the regularity behind these superficial facts. Therefore, the metaknowledge, defined as the knowledge about knowledge, is proposed to identify complex processes of knowledge production and consumption. Unfortunately, even though the current correlation-based rule mining methods in knowledge graph distill the rule-formed metaknowledge, they can not explain the processes of knowledge production. In this paper, we focus on capturing the metaknowledge with causality which is generally regarded as one of the most promising techniques to reveal the interactions between components in the complex system. To the best of our knowledge, this is the first attempt to interpret the knowledge graph from the causal perspective. For this purpose, we propose a causal metaknowledge method for link prediction, which achieves entity-level link prediction by discovering concept-level topological causality. Specifically, we first formalize causal metaknowledge as causal rule, following the form of logical rule. Then, we transform the relational data into propositional data to learn the causal relationships between topological structures. And an efficient algorithm for discovering local causal relationships is proposed using the d -seperation criterion. Eventually, the causal rules generated based on the mined relationships are used for link prediction. Both simulation-based and real data-based experiments demonstrate the effectiveness of the proposed approach, especially under the Out-of-Distribution(OoD) settings.

Distilling Causal Metaknowledge from Knowledge Graphs

Domain generalization (DG) seeks to learn robust models that generalize well under unknown distribution shifts. As a critical aspect of DG, optimizer selection has not been explored in depth. Currently, most DG methods follow the widely used benchmark, DomainBed, and utilize Adam as the default optimizer for all datasets. However, we reveal that Adam is not necessarily the optimal choice for the majority of current DG methods and datasets. Based on the perspective of loss landscape flatness, we propose a novel approach, Flatness-Aware Minimization for Domain Generalization (FAD), which can efficiently optimize both zeroth-order and first-order flatness simultaneously for DG. We provide theoretical analyses of the FAD’s out-ofdistribution (OOD) generalization error and convergence. Our experimental results demonstrate the superiority of FAD on various DG datasets.

Flatness-Aware Minimization for Domain Generalization

Popular Tasks used by Researchers

How can I help with your research?

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

We encountered an error while loading the panel. Please try refreshing the page.

Something went wrong

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

Anyone with the link can view this chat. You can switch it back to private anytime.

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Yancheng Dong

Author Tools

Chat about Author

Papers

Purify and Generate: Learning Faithful Item-to-Item Graph from Noisy User-Item Interaction Behaviors

Breaking Filter Bubble: A Reinforcement Learning Framework of Controllable Recommender System

Distilling Causal Metaknowledge from Knowledge Graphs

Flatness-Aware Minimization for Domain Generalization